Such a scrub brush is known from U.S. Pat. No. 4,377,878. At the periphery of the shaft of the scrub brush, soft pliant wash elements made from felt and stiff bristles are arranged in an alternating manner in the circumferential direction. The bristles are distinctly shorter than the wash elements and serve as support elements for them. The bristles are not involved in the washing process, nor are they washing elements. The washing of the vehicle is accomplished only by the soft pliant wash elements made of felt or another fibrous material. Although such wash elements are advantageous when used for gently washing a vehicle, they do not provide an optimal cleaning action.
German Utility Model DE-U-92 14 265 shows a scrub brush with a mixture of bristle-like coarse wash elements and strip-like soft wash elements made from a fibrous web. The scrub brush here is divided into several segments along its length, and the different wash elements alternate in the axial direction of the brush. There are bristles at the upper and lower region of the vertical side brush, while the softer fibrous web strips are arranged in the center region. The bristles and the fibrous web strips have the same length here. The bristles possess good cleaning ability and are even able to loosen and remove stuck-on dirt, but there is the danger of them causing minor damage to the surface being cleaned.
A similar scrub brush is known from U.S. Pat. No. 3,613,140. This is designed as a horizontal wheel washing brush and consists of various wash elements, which differ in material and length and are arranged in an alternating manner in the lengthwise direction of the brush. The longer wash elements are supposed to reach the insides of the vehicle's wheel or rim and consist of a soft bristle-like material. The shorter and likewise bristle-like wash elements are supposed to clean the exterior wheel and rim areas and are harder or stiffer than the longer bristles. They should consist of nylon or metal wire.
German Utility Model DE-U-93 01 692 shows another vertical side brush, which is designed similar to the aforesaid side brush of DE-U-92 14 265. Here as well, the side brush has only bristles in the lower region and textile strips in the upper region; furthermore, shorter supporting bristles can be arranged. The bristles and textile strips have the same length, while the bristles for the support function can also be shorter.
European Patent Application EP-A-0876778 shows a washing device for car wash units that has bristles of different length, and these bristles may also have different stiffnesses.
Therefore, the problem is to modify a generic washing device so that an improved and more thorough washing of vehicles is made possible.